Process for the manufacture of glossy and hollow artificial threads



i 45 out.

a '50 acter of differences in the actual steps of the methods. I

Patented July 7, 1925.

UNITED STATES P'ATE I 1,544,631 NT OFFICE JAQUES EDWIN BRANDENBEBGEB,

SOGIE'I'E mm: ALsA s. A.

or NEUILLY sun SEINE, raANcE, Assmnon T LA SIEGE socIAL; A BALE, SWITZERLAND.

rnocnss For. THE mANUrAc'rUaE or GLOSSY AND nonnow ARTIFICIAL 'rHanAns;

No Drawing.

To all whom it may concern:

Be itknown that I, J AQUES EDWIN BRANDENBl-IRGER, citizen of the Republic of Switzerland, residing at Neuilly sur Seine,

6 France, have invented certain new and useful Improvements in a Process for the Manufacture of Glossy and Hollow Artificial Threads, of which the following is a specification.

The method usually restored to in the manufacture of artificial hollow thread is to extrude or otherwise obtain thread from a solution of viscose containing either air or another neutral gas emulsified or dissolved in the said solution; or a substance capable of producing a hollow gaseous core or axial space in the thread after it is formed. The methods which involve the emulsifying and dissolving of air or other neutral gas in the viscose solution are described and claimed,

respectively, in in perior Patent, No. 1,394,-

270, granted Octo er 18, 1921, and in Patent No. 1487,807, granted March 25, 1924, to

Jules ltousset; while that involving the addition of a substance which will produce gas bubbles within the threads or other articles by thermal or chemical reaction is described and claimed in Patent No. 1,427,-

330, granted August 29, 1922, to the said Jules Rousset.

Investigation made on threads produced as just described have shown that the said space or core was generally not continuous throughout the thread, as it had partitions at unequal distances apart. The internal space was therefore divided into chambers of dissimilar length and strictly speaking the thread was not tubular. I

This invention relates to improvements in the above-described methods, of manufacturing hollow artificial thread as disclosed in the patents identified, the said improvements aiming at providing a thread with a hollow core practically continuous through- Reference may be had to theaforesaid patents for a complete explanation of the details of the patented methods, the improvements constituting the present inven 1 tion havin reference to the nature'or chartlie :viscose itself rather than to The thread made according to known meth ods and having a non-continuoushollow core "an above described has a dull and woolly appearance whereas the thread according to any other Application filed January 30, 1924. Serial No. 689,585.

this invention has the gloss of natural or artificial silk.

Viscose having the same character was hitherto used for the manufacture of hollow artificial thread and of ordinary artificial silk thread alike. This nature or character of the viscose being hereinafter referred to as degree of ripening and salt point, a definition of the ripening or salt point of viscose is necessary, and is as. follows: The salt point of a viscose corresponds, in a solution of sodium chloride, to the degree of concentration of the same just sutiicient to coagulate a drop of viscose dropped therein. Thus in the ordinary manufacture of artificial silk, a ripened viscose solution is said to havefor instance a salt point 3 and a recently prepared and therefore very little ripened viscose is said to have for example a 'salt point 13, this terminology meaning that the first-mentioned viscose is just coagulated in a 3% aqueous solution of sodium chloride and the second-mentioned viscose in a 13% solution. It may be easily inferred that the greater the degree of ripening, the lower the salt point.

Low salt point viscose (seldom above 4) is used in the ordinar methods of manufacture of artificial si k, owing to the circumstance that the coagulation is the easier the higher the degree of ripening. Viscose with a high salt point needs a comparatively highly concentrated coagulating solution which is liable to lower the quality of the final roduct and which unnecessarily entails urther difficulties in the manufacture.

As reviously stated, viscose having the same egree of ripeness 'was hitherto used in the manufacture of hollow artificial thread and of ordinary artificial thread alike, the outcome thereof being a hollow thread dull in appearance and with a discontinuous gaseous core.

The present inventionprovides a hollow and glossy thread with uniform and continuous gaseous core by extruding or otherwiseworking a viscose having a, low degree of ripening and containing either air (or neutral gas in suspension or in solution), or a substance capable of producing a gaseous core within the formed thread. This is therefore'a viscose having a high salt int, and more accurately, higher than 7.

f course the diameter of the thread to be produced must be taken into consideration when selecting a viscose having a. salt polnt above the minimum of 7 The artificial thread made according to this invention is glossy and uniformly tubular.

The quality of silk is denoted by the number of yards to the denier (a weight equal to 24 grains). The above-mentioned viscose with a salt point above 7 is suitable for manufacturing eight-denier thread, but the said salt point must not be below 10 to produce four-denier thread, assuming the circumstances to be the same.

Obviously the proce% according to this invention may be applied to the manufacture of hollow thread of any shape.

I claim as my invention:

1. The herein-described process, consisting in forming a lustrous hollow thread or filament from a solution of mildly-ripened viscose.

2. The herein-described process, consisting in forming a lustrous hollow thread or filament from a solution of viscose having a salt-point which is not less than 7.

3. The herein-described process, consisting in forming a lustrous hollow thread or filament from a solution of viscose having a salt-point which is above 7.

4. The herein-described process of manufacturing lustrous hollow artificial silk threads, consisting in incorporating in a. solution of mildly-ripened viscose a substance which will form bubbles in the threads; and then subjecting the resultant solution to treatment to form the threads.

5. The herein-described process of manufacturing lustrous hollow artificial silk threads, consisting in incorporating in a solution of viscose having a salt-point which is not less than 7, a substance which will form bubbles in the threads; and then subjecting the resultant solution to treatment reform the threads.

6. As a new article of manufacture, a his trous hollow artificial silk thread made from mildly-ripened viscose.

As a new article of manufadture, a lustrous hollow artificial thread made from viscose having a salt-point which is not less than 7.

8. As a new article of manufacture, a. lustrous hollow artificial silk thread made from mildly-ripened viscose having an internal series of elongated bubbles of gaseous fluid.

9. As a new article of manufacture, a lustrous artificial silk thread made from mildly-ripened viscose having fir internal series of bubbles of gaseous fluid, the bubbles being elongated to the point Where they virtually form a continuous hollow core.

In testimony whereof I afiix my signature.

JAQUES EDWIN BRANDENBERGER. 

